Attributes Reference

Attributes are written with @name or @name(args...) before declarations. The current language has a closed attribute table: unknown source attributes are rejected, and user-defined decorators are not part of 0.0.0-dev.

@deprecated("use new_fn instead")
fn old_fn() {}

@discardable
fn side_effect() -> i32 {
    return 42;
}

Attribute	Allowed targets	Arguments	Effect
@export / export	Top-level declarations and globals	none	Exports the declaration from the module interface. See Visibility and Privacy.
@extern / extern	Top-level functions and globals	none	Declares a Zynx-linkage symbol whose body is provided by another object or module unit.
foreign	Top-level functions and globals	ABI string; optional library block	Declares a non-Zynx ABI symbol. Only foreign "C" and foreign library "name" { abi "C"; ... } are accepted in 0.0.0-dev.
@symbol	foreign declarations	one string literal	Uses the named foreign symbol while keeping the Zynx declaration name local.
@intrinsic / intrinsic	Functions and methods	none	Marks a compiler/runtime intrinsic declaration. Normal source cannot define new intrinsic behavior.
@inline	Functions and methods	none	Codegen inline hint. Rejected with external declarations.
@discardable	Functions and methods	none	Suppresses ignored-result warnings for calls.
@deprecated	Functions and methods	optional string literal	Emits a deprecation warning on calls.
@weak	Functions and methods	none	Emits weak linkage for generated definitions.
@section	Functions and methods	one string literal	Places the generated function in an object section.
@noreturn	Functions and methods returning void	none	Marks the generated function as not returning.
@unmangled	Functions, methods, and globals	none	Uses the source name as the emitted symbol name.
@packed	Structs and unions	none	Uses packed source-order layout. Rejected with @strict.
@strict	Structs and unions	none	Uses source-order layout with target ABI alignment and padding. Rejected with @packed.
@native	Structs, unions, enums, and errors	none	Declares C-compatible aggregate or enum layout where supported by FFI rules.
@c_name	Structs, unions, enums, errors, and globals	one string literal	Records the C spelling used by bindgen/header emission.
@private	Struct fields and methods	none	Applies the private field and method rules from Visibility and Privacy.
@readonly	Struct fields	none	Rejects assignment to the field after initialization.
@bits	Fields of @native struct	one integer literal	Declares a native bitfield width.
@derive(json)	Structs	json	Enables typed std.json.decode<T> support for the struct.
@json_allow_unknown	Structs with @derive(json)	none	Allows typed JSON decoding to ignore object fields that do not map to struct fields.
@json_key	Fields of structs with @derive(json)	one string literal	Uses the named JSON object key for the field.
@json_optional	Fields of structs with @derive(json)	none	Allows the field to be absent and keeps the field default.
@json_skip	Fields of structs with @derive(json)	none	Ignores the field during typed JSON decoding.
@suppress	Locals and declarations	warning names	Suppresses supported warning kinds for that declaration.
@unused	Local bindings	none	Marks the binding as intentionally unused.
@abi	Top-level declarations and methods	one string literal	Includes a declaration only for a matching target ABI.
@arch	Top-level declarations and methods	one string literal	Includes a declaration only for a matching target architecture.
@platform	Top-level declarations and methods	one string literal	Includes a declaration only for a matching target platform.

Attribute validity depends on declaration kind and modifier ordering. The compiler reports duplicate or misplaced attributes. Duplicate attributes are rejected except for repeated @suppress(...).

export, extern, and intrinsic can also be parsed as declaration modifiers; the parser represents them internally as synthesized attributes. foreign is a separate declaration form for non-Zynx ABI boundaries.

Methods without a first self parameter are static methods. The old @static method attribute is not part of the current source surface.

Names beginning with __zynx_ are reserved for compiler-private generated code and are not a stable user extension mechanism.

LLVM hooks such as @llvm.memcpy and @llvm.uadd.with.overflow are compiler builtins used in expressions, not declaration attributes.